I know a guy who got one of those Russian “mail order” brides. They had a kid together and then she divorced him as soon as she became a citizen, leaving the kid with him. She married some other guy eventually and still sees the kid, but she doesn’t pay child support. My friend comes from a traditional Asian culture and is significantly older than her. The sad thing is that he was shocked when she left, since they got along fine. I don’t think it was a scam exactly. More of a transactional relationship and she no doubt felt that she held up her end of the bargain for a reasonable enough amount of time (about 5 years, if I recall) and gave my friend a child on top of the marriage.